Diagnosis. (1) Five supraoculars (rarely four or six), first supraocular is the longest, second largest in area; (2) last supraocular contacts three ciliaries (rarely two); (3) ventral side of head usually with heavy mottling and black spots; (4) largest pre-femoral scales are imbricate, hexag- onal, and longer than tall; (5) two enlarged supratemporal scales, a second row of enlarged but smaller scales ventral to the two enlarged scales; (6) one occipital usually contacts the interpar- ietal; (7) rostral is readily visible in dorsal view; (8) adult dorsum often has transverse bands that fade with age but are still distinct, does not hold true for the Trinidad and Tobago popula- tions which usually retain well defined bands into adulthood; (9) the anterior corner of the orbit is usually over upper labial four or the seam of upper labials three and four. This species corresponds to clade 4 in the molecular analysis.

Variation. Temporal scales mostly oval; posterior border of frontal extends posterior to the border of the second and third supraocular in Trinidad specimens examined, but not in Tobago specimens; the frontal is about equal to, or slightly shorter than frontoparietals (frontal is longer than frontoparietals in other species); 8–1 ciliaries, two in contact with last supraocu- lar; 8–9 rows of temporal scales in Trinidad specimens 11 rows in Tobago specimens; 8–1 upper labials, last one or two upper labials are usually hexagonal in Trinidad specimens, in Tobago specimens the last several upper labials are pentagonal), all others rectangular; 7–8 lower labials; lamellae on fourth finger 15–18; lamella on fourth toe 3–38; first pair of chin shields in medial contact, the other three pairs are separated by multiple scales; 3–7 occipitals in contact with parietals in Trinidad population; 11 occipitals in contact with parietals in the Tobago population; 8–14 preanal pores, 12–23 femoral pores per side, 23–36 total pores. The cloacal plate has seven or eight rows of scales from the level of the femoral pores to the free edge of the plate, five of these rows are plate-like scales.In alcohol the head is olive green with some dark spotting on the crown scales. The lower jaw is yellow and heavily mottled with black pigment. The dorsum of the neck and body is mostly uniform dark brown to black with about 12 rows of indistinct spots. The ventral surface is mostly yellow with dark pigment intruding from the side along the seams of the ventrals, and some patches of dark pigment scattered. This same coloration occurs on the underside of the legs. Proximally, the tail is a solid dark brown-black above with very narrow yellow rings. Juve- nile coloration (based on UWIMZ 212.27.42) is black with markings. Light spot on frontal, and supraoculars outlined in white, stripe on seam of frontoparietals; face mostly gray, with black postocular stripe extending over ear, anterior upper labials gray, posterior upper labials outlined in black; lower labials white with black seams; chin white; dorsum black with 11 irreg- ular, interrupted white cross bands; venter white with scattered black checks; forelimbs banded with alternating black and white bands; hind limbs have irregular elongated yellow markings on dorsal surfaces with only a trace of black stripes on ventral surface; tail with alternating black and white bands, and a white/yellow tail tip. Coloration of juveniles and adults in life can be seen in Fig 1.There is considerable pattern variation in Tupinambis cryptus. Mainland Venezuelan speci- mens tend to have bands that are indistinct and short longitudinal stripes that Beebe [2] termed “dashes.” A few are almost uniform in coloration. None of the adults from Trinidad and Tobago have this pattern, although we have seen a few individuals in the field with indistinct bands.

Comparisons. Tupinambis cryptus sp. n. can be distinguished from the sometimes sympatric and syntopic T. teguixin by its lower number of vertebral rows (average 16 vs 116); three supratemporals (T. teguixin usually has two); one occipital contacting the interparietal (T. teguixin usually has three); three ciliaries contacting the last supraocular (T. teguixin has two); the dorsal surface of the hind legs is uniform in older adults with younger animals having irreg- ular vermiculations (T. teguixin has light colored round spots—but may also show reticula- tions); This species can be distinguished from T. cuzcoensis sp. n., by its lower vertebral scale row count (means 14 vs 119 in T. cuzcoensis); its longest supraocular is the first (in T. cuzcoen- sis sp. n. the second is longest); the species has a higher average number of scale rows around mid-body (16) compared to 98 in T. cuzcoensis; and the first pair of chin shields are longer than the postmental (T. cuzcoensis sp n has the first pair of chin shields shorter or about equal to the postmental in length). It can be distinguished from T. zuliensis sp. n. by having the first supraocular longer than the second.